High-quality repair of damaged Inconel 718(IN718)superalloy components can achieve great economic benefits.However,the directly double aging(DA)treatment by industrial standards,yields an inferior ductility on the rep...High-quality repair of damaged Inconel 718(IN718)superalloy components can achieve great economic benefits.However,the directly double aging(DA)treatment by industrial standards,yields an inferior ductility on the repaired component than that of the wrought base metal.In this work,wrought IN718 components were repaired by laser-directed energy deposition(LDED),a novel tailored heat treatment(THT)schedule consisting of a short-term low-temperature homogenization,and subsequent DA was sub-sequently conducted to strengthen the repaired IN718 alloys.The microstructure evolution and mechan-ical properties of the DA and THT-treated repaired alloys were comparatively investigated.The results indicated that the THT effectively dissolved most of the hard brittle Laves precipitates in the deposition region with only slight coarsening of the grains in the substrate.As compared to the DA sample,the elon-gation of the THT sample increased remarkably by 88%with only a slight reduction of 19.2 MPa in yield stress.Moreover,the strain distribution of the THT sample was overall more even but then destabilized in a narrow abnormal coarsened grain region caused by the static recrystallization.In general,this study breaks through the limitation of the low ductility of the DA-treated repaired IN718 alloys and provides a promising way to further improve the mechanical properties.展开更多
基金support from the National Natural Science Foundation of China(Nos.52275374 and 52205414)the Xiaomi Foundation through the Xi-aomi Young Scholar Program,the Key Research and Develop-ment Projects of Shaanxi Province(No.2023-YBGY-361)as well as the Young Elite Scientists Sponsorship Program by CAST(No.2021QNRC001).
文摘High-quality repair of damaged Inconel 718(IN718)superalloy components can achieve great economic benefits.However,the directly double aging(DA)treatment by industrial standards,yields an inferior ductility on the repaired component than that of the wrought base metal.In this work,wrought IN718 components were repaired by laser-directed energy deposition(LDED),a novel tailored heat treatment(THT)schedule consisting of a short-term low-temperature homogenization,and subsequent DA was sub-sequently conducted to strengthen the repaired IN718 alloys.The microstructure evolution and mechan-ical properties of the DA and THT-treated repaired alloys were comparatively investigated.The results indicated that the THT effectively dissolved most of the hard brittle Laves precipitates in the deposition region with only slight coarsening of the grains in the substrate.As compared to the DA sample,the elon-gation of the THT sample increased remarkably by 88%with only a slight reduction of 19.2 MPa in yield stress.Moreover,the strain distribution of the THT sample was overall more even but then destabilized in a narrow abnormal coarsened grain region caused by the static recrystallization.In general,this study breaks through the limitation of the low ductility of the DA-treated repaired IN718 alloys and provides a promising way to further improve the mechanical properties.
